MONDAY, May 20 (HealthDay News) -- Although many hospital intensive care units have a nighttime attending physician on staff to help improve outcomes, new research suggests this may have no clear benefit to patients.

Since one-third of teaching hospitals in the United States and three-quarters of hospitals in Europe staff a nighttime physician in the ICU, the practice may unnecessarily increase health-care costs while siphoning doctors away from hospitals with fewer resources, the study authors said.

"Based on these results, if an academic hospital's primary goal is to improve patient outcomes, then I don't think having an attending physician physically there overnight in a medical ICU is necessary," said the study's first author, Dr. Meeta Prasad Kerlin.

"This is an important finding that affects a lot of stakeholders. Staffing an intensivist [attending physician] at night is probably quite costly, because the total billing will likely be at a higher rate, which could trickle down to the insurance provider or patient. There's also the operating cost associated with staffing that impacts hospitals," said Kerlin, an assistant professor of medicine at the University of Pennsylvania School of Medicine's division of pulmonary, allergy and critical care.

The one-year study involved nearly 1,600 patients admitted to the ICU at the Hospital of the University of Pennsylvania.

The study's senior author, Dr. Scott Halpern, assistant professor of medicine, epidemiology, and medical ethics and health policy, and a team of researchers compared overnight ICU staffing. One staffing group included medical residents and an attending physician; the other group included an attending physician who was only available to medical residents by phone. The researchers also conducted in-hospital follow-up on the patients for 90 days.

The study found that nighttime physicians had no effect on how long patients stayed in the ICU, how long their hospital stay was, in-hospital death rates, ICU readmissions or discharge to home. The researchers said this held true even among the most critically ill patients or those admitted at night.

"This tells me that residents and nurses are well qualified and completely competent to handle these patients," Kerlin said in a news release from the medical school. "As long as nurses and residents have access to an on-call attending physician, then the patient will do as well as if the senior doctor was at their bedside."

The study also found that medical residents believe nighttime attending physicians provide needed support and enhance the doctors'-in-training learning experience. The researchers noted hospitals may want to consider residents' opinions when making a decision on this staffing issue.

The study was published online May 20 in the New England Journal of Medicine to coincide with a presentation at the American Thoracic Society International Conference in Philadelphia.